[bgpd] Trim memory usage of BGP routes

[bgpd] Trim memory usage of BGP routes

2007-05-03 Paul Jakma <paul.jakma@sun.com>

	* bgp_route.h: (struct info) Move less frequently used
	  fields to a lazily allocated struct info_extra.
	  Export bgp_info_extra_get
	* bgp_route.c: (bgp_info_extra_new) allocate extra
	  (bgp_info_extra_free) Free damp info and the info_extra.
	  (bgp_info_extra_get) Retrieve the info_extra of a struct
	  info, allocating as required.
	  (generally) adjust to use info->extra
	* bgp_damp.c: (generally) use bgp_info_extra_get to access
	  dampinfo
	* bgp_attr.h: Move rarely allocated attributes from struct attr
	  to a struct attr_extra, for a substantial saving in size of
	  struct attr.
	* bgp_attr.c: (bgp_attr_extra_{new,free}), new, self-explanatory.
	  (bgp_attr_extra_get) Get the attr_extra for a given struct
	  attr, allocating it if needs be.
	  (bgp_attr_dup) Shallow copy the struct attr and its attr_extra.
	  (generally) adjust to know about attr->extra.
	* bgp_debug.c: (bgp_dump_attr) ditto
	* bgp_vty.c: (show_bgp_memory) print attr and info extra sizes.
	* bgp_nexthop.c: (generally) adjust to know about attr->extra
	  and info->extra.
	* bgp_{packet,routemap,snmp,zebra}.c: ditto
	* lib/memtypes.c: Add MTYPE_ATTR_EXTRA and MTYPE_BGP_ROUTE_EXTRA